Don't start the watcher if dir doesn't exist

launcher/beatmapdirwatcher.go

@@ -4,6 +4,7 @@ import (
 	"github.com/fsnotify/fsnotify"
 	"github.com/wieku/danser-go/framework/goroutines"
 	"log"
+	"os"
 	"path/filepath"
 )
 
@@ -12,6 +13,13 @@ var watcher *fsnotify.Watcher
 func setupWatcher(file string, callback func(event fsnotify.Event)) {
 	var err error
 
+	abs, _ := filepath.Abs(file)
+
+	_, err1 := os.Lstat(abs)
+	if err1 != nil { // Beatmap dir not found, abort
+		return
+	}
+
 	watcher, err = fsnotify.NewWatcher()
 	if err != nil {
 		log.Fatal(err)
@@ -39,8 +47,6 @@ func setupWatcher(file string, callback func(event fsnotify.Event)) {
 		}
 	})
 
-	abs, _ := filepath.Abs(file)
-
 	err = watcher.Add(abs)
 	if err != nil {
 		log.Fatal(err)